JEJU, South Korea, Sept. 2 (Yonhap) -- The bloody 1948-1954 suppression of a civilian uprising on Jeju Island will be included in all history textbooks to be used in middle and high schools nationwide starting next year, the Jeju provincial office of education said Monday.

The Jeju April 3 incident occurred on April 3, 1948, when Jeju islanders began protesting against U.S. military-led rule following Korea's liberation from Japan's 1910-1945 colonial rule. The then government distorted the uprising as a communist riot and massacred up to an estimated 30,000 civilians in armed crackdowns over the subsequent years.

The Jeju education office said the content related to the April 3 uprising is included in all seven middle school history textbooks and all nine high school history textbooks, which have passed the Ministry of Education's review.

At present, the content is missing in two of the seven middle school textbooks.

The office also said it plans to ask the Korea Institute of Learning Evaluation, a private publishing company, to revise parts of the April 3 uprising-related content in its high school history textbook, noting it described the targets of suppression in the incident as "rebel forces."